HP Forums

Hello all.

During which body redesign did HP implement the ln(2.02) bug fix on the HP-35?

Firmware changes don't generally correlate well with mechanical changes.

US-made 35s with 1143-serial numbers (probably not all though) had the bug. If judging by the casing, I'd say it correlates more or less with the "raised dot" on the "5"-key". However a lot of calculators were sent back for service, the faulty ROMs were desoldered and replaced.